#include <stdio.h> int main() { double m = 0.0; double n = 0.0; char op = 0; //多组输入 while (~scanf(" %lf%c%lf", &m, &op, &n)) { switch (op) { case '+': printf("%.4lf+%.4lf=%.4lf\n", m, n, m + n); break; case '-': printf("%.4lf-%.4lf=%.4lf\n", m, n, m - n); break; case '*': printf("%.4lf*%.4lf=%.4lf\n", m, n, m * n); break; case '/': if (0 == n) { printf("Wrong!Division by zero!\n"); } else { printf("%.4lf/%.4lf=%.4lf\n", m, n, m / n); } break; default: printf("Invalid operation!\n"); break; } } return 0; }